<template>
  
  <view>
    <my-search @click = "gotosearch"></my-search>
    <view class="scroll-view-container">
      <!-- 左侧的滚动视图区域 -->
      <scroll-view class="left-scroll-view" scroll-y :style="{height: wh + 'px'}">
         <block v-for="(item, i) in cateList" :key="i">
           <view :class="[ 'left-scroll-view-item' , i === active ?'active' : '' ] " @click="activeChanged(i)">{{item.cat_name}}</view>
         </block>

      </scroll-view>
      <!-- 右侧的滚动视图区域 -->
      <scroll-view class="right-scroll-view" scroll-y :scroll-top="scrolltop" :style="{height: wh + 'px'}">
          <view class="cate-lv2" v-for="(item2, i2) in cateLevel2" :key="i2">
            <view class="cate-lv2-title">/ {{item2.cat_name}} /</view>
            <view class="cate-lv3-list">
              <view class="cate-lv3-item" v-for = "(item3,i3) in item2.children"  @click="gotoGoodsList(item3)">
                <image :src="item3.cat_icon"></image>
                <text>{{item3.cat_name}}</text>
              </view>
            </view>
          </view>
      </scroll-view>
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        wh:0,
        cateList: [],
        active:0,
        cateLevel2: [],
        scrolltop:0
      };
    },
    onLoad() {
          // 获取当前系统的信息
          const sysInfo = uni.getSystemInfoSync();
          // 为 wh 窗口可用高度动态赋值
          this.wh = sysInfo.windowHeight - 50;
          
          this.getCateList();
          
        },
        methods:{
              async getCateList() {
                // 发起请求
                const { data: res } = await uni.$http.get('https://api-hmugo-web.itheima.net/api/public/v1/categories')
                // 判断是否获取失败
                if (res.meta.status !== 200) return uni.$showMsg()
                // 转存数据
                this.cateList = res.message
                console.log(this.cateList)
                this.cateLevel2 = this.cateList[0].children;
                
              },
              activeChanged(i){
                this.active = i;
                this.cateLevel2 = this.cateList[i].children;
                this.scrolltop = this.scrolltop === 0 ? 1 : 0;
               
              },
              gotoGoodsList(item3){
                  uni.navigateTo({
                    url: '/subpkg/goods_list/goods_list?cid=' + item3.cat_id
                  })
              },
              gotosearch(){
                uni.navigateTo({
                  url:"/subpkg/search/search",
                })
              }
        }
  }
</script>

<style lang="scss">
  .scroll-view-container {
    display: flex;
  
    .left-scroll-view {
      width: 120px;
  
      .left-scroll-view-item {
        line-height: 60px;
        background-color: #f7f7f7;
        text-align: center;
        font-size: 12px;
  
        // 激活项的样式
        &.active {
          background-color: #ffffff;
          position: relative;
  
          // 渲染激活项左侧的红色指示边线
          &::before {
            content: ' ';
            display: block;
            width: 3px;
            height: 30px;
            background-color: #c00000;
            position: absolute;
            left: 0;
            top: 50%;
            transform: translateY(-50%);
          }
        }
      }
    }
  }
  .cate-lv2-title {
    font-size: 12px;
    font-weight: bold;
    text-align: center;
    padding: 15px 0;
  }
  
  .cate-lv3-list {
    display: flex;
    flex-wrap: wrap;
  
    .cate-lv3-item {
      width: 33.33%;
      margin-bottom: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
  
      image {
        width: 60px;
        height: 60px;
      }
  
      text {
        font-size: 12px;
      }
    }
  }
</style>
